Ecnomus japonicus Fischer 1970

Kuhara, Naotoshi, 2016, Revision of Japanese species of the genus Ecnomus McLachlan (Trichoptera: Ecnomidae), with descriptions of two new species, Zootaxa 4114 (5), pp. 561-571 : 566-568

Ecnomus japonicus Fischer 1970

( Figs. 4 A–D, 6)

Ecnomus serrata Kobayashi 1959: 347 –348, fig. 3, male [type locality: Japan, Kyûshû, Fukuoka, Yoshii]. Preoccupied by Ecnomus serratus Ulmer 1930 . (Type not seen.)

Ecnomus japonicus Fischer 1970: 242 . [replacement name for Ecnomus serrata Kobayashi ] Ecnomus tsudai Kumanski 1992 , 62–63, figs. 35–40, male, female [type locality: North Korea, Province Pyǒngannam-do] New synonym.

Diagnosis. The upturned apices of the male inferior appendages of this species are similar to those of E. connatus Li & Morse 1997 from China, but E. japonicus can be distinguished from the latter by the shape of the superior appendages, which are parallel-sided in lateral aspect; and the parameres, which are flattened and boot-shaped. These boot-shaped parameres are also unique among Japanese species. The female is distinguished from the other Japanese species by the combination of the lack of a ventromesal plate of sternum VII and the large ventral plates of segment VIII.

Description. Adult ( Fig. 4 ). Length of each forewing of male 4.7–5.4 mm (mean = 5.2 mm, n = 6), female 5.2–5.4 mm (mean = 5.3 mm, n = 4). Warts on head and thorax similar to those of E. hokkaidensis sp. nov. except as follows: Preocellar warts on head vertex subtriangular ( Fig. 4 A); frons with pairs of large dorsal hypomedial warts and distinct small ventral hypomedial warts ( Fig. 4 B); medial warts on pronotum slightly larger than in E. hokkaidensis ( Fig. 4 A). Venation similar to E. hokkaidensis but forewing crossvein m-cu meeting median vein well before bifurcation of medial vein ( Fig. 4 C).

Male genitalia ( Figs. 4 D–H). Tergum IX short, about 1/2 as long as sternum IX ( Fig. 4 D); anterodorsal margin shallowly excised ( Fig. 4 F); sternum IX without longitudinal median line ( Fig. 4 E); in lateral aspect ventral margin nearly linear, dorsal margin expanded around midlength ( Fig. 4 D); in ventral aspect anterior and posterior margins shallowly excised ( Fig. 4 E). Segment X represented by pair of short broad plates, each triangular in dorsal aspect with 3 setae apically ( Fig. 4 F). Superior appendages elongate, parallel-sided with rounded apices in lateral aspect ( Fig. 4 D), inner surfaces with black stout peg-like setae in apical 1/4; finger-like projection arising from each ventrobasal corner, with 2 or 3 setae apically ( Fig. 4 F). Inferior appendages extending to or slightly beyond posterior end of superior appendages, upcurved preapically ( Fig. 4 D); basal plate semisclerotized, with pair of small narrow lateral projections at 1/3rd distance from anterior end ( Fig. 4 G). Phallus bulbous basally, acute apically; parameres moderately sclerotized, short, flattened, boot-shaped in lateral aspect, directed posterodorsad; dorsobasal lobe distinct ( Fig. 4 H).

Female genitalia ( Figs. 4 I, 4J). Ventromesal plates of sternum VII absent. Ventral plates of sternum VIII large, subquadrate in lateral aspect, each with 3 long setae along apical margin ( Fig. 4 I); outer surfaces slightly sinuate ( Fig. 4 J). Segment X short ( Fig. 4 I). Segment XI setose, well pigmented ( Figs. 4 I, 4J).

Specimens examined. [Hokkaidô] Rumoi: 6 females, Rumoi-shi, Ôwada, Rumoi-gawa, el. 10 m, 2.viii.2015, NK. [Honshû] Ibaraki: 1 male, Takahagi-shi, Yokokawa, Oyama-dam, 17.vii.2010, N. Katsuma. Kanagawa: 1 male, Sagamihara-shi, Mikage, 28.v.2007, N. Katsuma. Mie: 1 male, Ise-shi, Kôraibiro, 4.ix.2004, H. Morita; 1 male, Ise-shi, Tsurugi-tôge, 15.vi.2002, H. Morita; 3 males, Kumano-shi, Kiwachô, 12.viii.2009, H. Morita. Shiga: 1 female, Higashiômi-shi, Yuzurio-chô, Kanzaki-gawa, Kazaoka-dani, el. 380 m, 6.ix.2013, TI; 1 male, Yogo-chô, Suganami, 6.viii.2008, T. Ushijima. Kyôto: 1 male, Ayabe-shi, 16.ix.2006, NK; 1 male, Sonobe-chô, 22.viii.2000, S. Tsukaguchi. [Shikoku] Tokushima: 5 males, 3 females, Aioi-chô, Taniuchi-gawa, 3.ix.2004, S. Tsukaguchi; 1 male, Kamiyama-chô, Minamigyôshano, Akui-gawa, 28.v.2004, K. Nio. Kôchi: 1 male, Niyodo-mura, Mori, 11.vii.2004, M. Takai. [Kyûshû] Fukuoka: 1 female, Hisayama-machi, Ino, Todoroki-gawa, 21.ix.2000, AO. [Tsushima] 2 males, 2 females, Tsushima-shi, Kamiagata-cho, Sago, 1.5 km South of Kônoki-yama, 22- 23.vii.2009, R. B. Kuranishi. [ Korea] 2 males, 2 females, Gyeongsangbuk-do, Cheongdo, Unmun-myeon, Sinwonri, 30.viii.2015, S. Inaba & S. Park.

Distribution. Japan: Hokkaidô, Honshû, Shikoku, Kyûshû, Tsushima. Korea, Russian Far East (Khabarovsk and Primorye Territories).

Habitat. Adults were collected beside a lowland river in Hokkaidô.

Remarks. The male genitalia of Ecnomus tsudai Kumanski , described from Korea is essentially identical to that of this species judging from the original description ( Kumanski 1992) and examination of Korean specimens. Thus, I conclude that E. tsudai is a junior subjective synonym of E. japonicus . Ecnomus japonicus belongs to the E. connatus Group of Li & Morse (1997), because the phallus is bulbous basally and acute apically, the superior appendages are elongate, and sternum IX lacks longitudinal median line.

Figures

FIGURE 4. Ecnomus japonicus Fischer (Sikoku, Tokushima, Taniuchi-gawa). 4 A, head, prothorax and mesothorax, dorsal; 4 B, head, frontal; 4 C, right wings, venation, dorsal; 4 D – 4 F, male genitalia: 4 D, left lateral; 4 E, dorsal; 4 F, ventral; 4 G, male phallus and inferior appendages, dorsal; 4 H, phallus, left lateral; 4 I – 4 J, female genitalia: 4 I, left lateral; 4 J, ventral.